SURD Synonyms: 127 Similar and Opposite Words

surd

adjective

Definition of surd

as in irrational

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Recent Examples of Synonyms for surd

Adjective

The industrial revolutions of the past produced enormous value alongside bankruptcies, dislocations, and periods of irrational exuberance.

— Brian Solis, Forbes.com, 5 Oct. 2026
If anyone can reconstruct Apéry’s reasoning, the odd values of zeta may finally be proven irrational.

— Lyndie Chiou, Scientific American, 2 Oct. 2026

Definition of irrational

Adjective

But that’s illogical, given the enormous ratings for the Seahawks–Patriots game, which was shown on the NBC broadcast network and the Peacock streaming service.

— Brian Stelter, CNN Money, 15 Sep. 2026
Trump's resumption of his illogical on-again, off-again trade war with our ally to the north has caused considerable economic concern in Canada, but has also activated a rush of resilience that Republicans in America can only dream of.

— Chris Brennan, USA Today, 10 Sep. 2026

Definition of illogical

Adjective

But in each event—in the living act, the undoubted deed—there, some unknown but still reasoning thing puts forth the mouldings of its features from behind the unreasoning mask.

— Literary Hub, Literary Hub, 6 July 2026
Roosevelt surely understood that nameless, unreasoning, unjustified fear cannot be eradicated.

— New York Times, New York Times, 9 June 2026

Definition of unreasoning

Adjective

But Michael Edney, who worked at the OLC under Bush, said the opinion’s reading of executive privilege was not unreasonable, given the importance that some presidents place on outside consultation.

— Perry Stein, Washington Post, 18 Oct. 2026
Both sides have accused each other of being unreasonable and of ignoring practical concerns about voting and election security, though in very different ways.

— Kevin Rector, Los Angeles Times, 17 Oct. 2026

Definition of unreasonable

Adjective

Or maybe he was lured into his thoughtless comments because of the jocularity inside that room full of reporters.

— Candace Buckner, New York Times, 16 Sep. 2026
At the outset of this chatty novel, the protagonist, Caroline, who was recently ghosted by a thoughtless man, has had a story published in this magazine.

— The New Yorker, New Yorker, 10 Aug. 2026

Definition of thoughtless

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surcoats

surd

sure

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“Surd.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/surd. Accessed 20 Oct. 2026.

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Synonyms of surd

adjective

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